1. Field of the Invention
The present invention relates to hand sprays used e.g. on kitchen sinks as alternative or additional water sources to the main tap or faucet.
2. Summary of the Prior Art
Typical hand sprays (also known as side sprays) include a spray head, e.g. similar to a shower head, for delivering fluid (e.g. water) flow through a nozzle. Traditionally, the hand sprays are located next to the primary tap or taps of a kitchen sink. Side sprays are commonly used with mixer taps. The spray head typically included a hand grip to allow the user to direct the flow as desired. Some hand sprays are removably mountable on the work surface (sink holding or containing surface) and have a flexible fluid delivery hose to allow more freedom of movement. Typically, known hand sprays are operable using a simple thumb switch, which controls a valve to stop or release fluid flow through the nozzle. The thumb switch allows controlled one-handed operation.
Early hand sprays were connected to a single source, e.g. the cold water supply pipe for the primary tap. The lack of control over hand spray output temperature was undesirable, so a number of proposals to provide mixed (e.g. hot and cold) water, preferably controllably mixed water, at the hand spray were made.
In one proposal an automatic diverter valve is incorporated into a mixer tap. The diverter valve operates to deflect mixed water into the hand spray when the hand spray is operated. To fit in the mixer tap, the automatic diverter was small, which meant that in time it was liable to become clogged with limescale and therefore reduce flow to the spray.
Automatic diverters made the use of bridge mixer taps difficult. To address this, GB 2361047 proposes a bridge mixer tap with a mixer chamber separate from the traditional mixer passageway between tap pillars. The extra mixer chamber is located under the work surface, where it is fed by hot and cold water supplies controllable by valves (also located under the work surface) operable by the tap operators on each pillar. The mixing chamber possesses two outputs: one feeds a hand spray via a flexible conduit, the other sends mixed water up through both pillars to be ejected from the main tap spout. A valve in the mixing chamber shuttles between two positions according to pressure differential experienced in the mixing chamber (due to operative status of the hand spray) to direct flow through a respective one of the outputs. In this arrangement, long operator shafts are required to extend down the pillars to their respective valves, and the visible mixing passageway is redundant because the water is already mixed when it reaches that passageway.
GB 2394525 proposes a bridge mixer tap arranged to address the above-mentioned problems by providing a built in diverter valve in the traditional bridge mixing chamber (above the work surface). The diverter valve can divert mixed flow down a passageway coaxial with one of the pillar input supplies so that it flows back beneath the work surface after mixing, where it is sent through a flexible conduit to feed a hand spray device. This avoids having a redundant bridge mixer passageway, but increases the complexity of the tap units. For example, the size of the bridge mixer may be enlarged to house the diverter valve. The temperature of the mixed water is controlled by the tap operators on the pillars.